1. Field of the Invention
This invention relates to an image recording member for recording an image by application of electricity, which is usable in recording various signals such as those of fascimile recording, computer output and its terminal equipment, data from various kinds of measuring instruments for industry, medicine, business and the like.
2. Description of the Prior Arts
With developments in facsimile recording and the like, recording of electrical signals in the form of images has been increasing as the years go by. The most widely used conventional techniques to meet such demands are, for example, electric discharge recording and electrolytic recording.
In electric discharge recording, however, there exist various disadvantages such as very strong and irritating smell which results from recording, dust from perforation of the surface layer, and stylus wear as a result of the discharge recording, because the surface layer of the recording member is perforated by electric discharging heat from the stylus.
Moreover, owing to bending, pressure-adhesion, and other mechanical forces, the black layer of the recording member is liable to be exposed outside to stain the recording paper. In addition, the surface layer of the recording member is made thin to facilitate generating the required electric discharge, hence the black layered base cannot be concealed perfectly thereby causing the recording member as a whole to assume a greyish color rather than pure white and thereby reducing the quality of the recording member.
On the other hand, in electrolytic recording, preservation of the recording paper is not satisfactory, as the method is of a wet type and the quality of the recorded image is affected by the amount of the toner. Furthermore, after the completion of the image recording, the recording paper is subjected to deformation such as waving and the like, due to drying. Such phenomena are all ascribable to the inherent defects of the wet method.
In order to solve these various defects in conventional recording methods, various new methods have been attempted such as disclosed in Japanese Patent Publications No. 38-22341, No. 44-29630, No. 42-5476, and No. 42-13239.
In Japanese Patent Publications No. 38-22341 and No. 44-29630, there is proposed the use of a dry type electro-sensitive recording sheet to obtain an image by dispersing an electrically reducible metallic compound in an electrically insulating resin, and then reducing the metallic compound to the free metal by electric conduction. In this type of recording sheet, however, most of the metallic compounds having relatively high electric conductivity are colored, and those metallic compounds which are less colored have a low electric conductivity. Therefore, in order that such metallic compounds of low electric conductivity may be properly electrically conductive, both chemical and physical treatment becomes necessary. By such treatment, however, the metallic compounds are colored with the consequence that the color density of the base sheet becomes considerably high. Moreover, in view of the fact that the metallic compound is low in electrical conductivity, there occurs electric discharge at the time of the recording and the heat from this electric discharge brings about bad smell, or causes the stylus to wear out considerably.
Further, in Japanese Patent Publications No. 42-5476 and No. 42-13239, there is proposed a method wherein an electrically conductive coating is formed by use of the evaporative deposition method onto a white or transparent material such as silica, and so forth, after which the combination of the base material and the electrically conductive coating are dispersed in a matrix for electric conduction. This method, however, requires considerable skill in the process for treating the same.
As stated in the foregoing, even in the electro-sensitive recording medium of the heretofore known type, no satisfactory result could be obtained.
In view of these facts, the present inventors have proposed an entirely novel dry type electrically conductive recording method and the recording material to be used therefor with a view to eliminating various defects in the conventional electrically conductive recording method or recording material.
This proposal, in summary, is characterized in that, in the method of electrically recording an image, binary components of (A) a zeolitic water containing compound, and (B) an image former are caused to be present in the recording medium, and the required image is formed by carrying out electric conduction through the recording medium. The proposal also is directed to the electrically conductive recording material to be used for carrying out such method. As a whole, the proposal made by the present inventors is to utilize the electric conductivity of the zeolitic water containing compound so as to effectively render color-development of the image forming agent for the desired image recording.
However, even in the recording member as proposed by the present inventors further improvement is required, particularly, of amplification in the color development reaction of the color developing component, stability of the recorded image against lapse of time, stability in preservation of the recording member per se, and so on.